1. Field of the Invention
The invention relates to an automotive milling machine, as well as to a method for steering an automotive milling machine.
2. Description of the Prior Art
The automotive milling machine, in particular road milling machine or surface miner, comprises a machine frame with longitudinal axis, a chassis with wheels or tracked travelling drive units supporting the machine frame, as well as a controller for the travelling, steering and milling operation and a height-adjustable working drum. A slewable last or single transport conveyor of specified length is arranged in front of or behind the working drum as seen in the direction of travel of the milling machine, where said transport conveyor is, as a minimum, slewable sideways about an essentially vertical first axis under a slewing angle.
The milling machine comprises a controller for the travelling and milling operation, as well as a working drum for the milling of, for example, a road pavement. A transport conveyor device comprising no less than one transport conveyor is located in front of or behind the working drum as seen in the direction of travel. The last or single transport conveyor of the transport conveyor device as seen in the direction of transport may be slewed sideways, relative to the longitudinal axis of the milling machine, under a specifiable slewing angle to the left or right and may be adjustable in height via a specifiable elevation angle. The transport conveyor device comprises a discharge end at which the milled material is discharged onto the loading surface of a transport vehicle via a flight path in the form of a parabolic trajectory that is attributable to the conveying speed and the elevation angle.
In practical operation of such a milling machine, problems caused by the widely projecting transport conveyor arise when steering the milling machine during operation and when relocating the milling machine to a different position.
With a front-loading milling machine, for example, the milled material is discharged towards the front onto the transport vehicle driving ahead. The operator of the milling machine needs to signal to the vehicle driver of the transport vehicle as to when the transport vehicle is to continue moving forward. This leads to problems because the operator basically needs to concentrate on the milling process and at the same time needs to avoid a collision with the transport vehicle driving ahead.
An additional problem lies in the fact that the operator of the milling machine also needs to deal with loading the loading surface by adjusting the slewing angle, elevation angle and conveying speed of the last or single transport conveyor of the transport conveyor device as seen in the direction of transport and is thus distracted from his actual task, which consists in carrying out the milling process. A correction of the slewing angle may be required, for example, when altering the direction of travel of the milling machine.
In case of a rearward-loading milling machine, problems also arise in coordinating the milling machine with the transport vehicle especially as the transport vehicle needs to drive behind the milling machine in reverse travel. An even higher level of stress results for the operator of the milling machine as he needs to control the milling process in forward travel on the one hand, and needs to monitor loading of the transport vehicle behind the milling machine as seen in the direction of travel, needs to control the slewing angle, elevation angle and/or conveying speed of the transport conveyor device, and needs to communicate the necessary information to the vehicle driver on the other.
When relocating the automotive milling machine to a different position, the operator of the milling machine must make sure that the widely projecting transport conveyor does not collide with any lateral obstacles, such as poles, along a track in particular when cornering narrow bends. The transport conveyor may be longer than the actual milling machine and usually measures approx. 5 m to approx. 8 m in length.